Start work on handling multibuffers properly when closing unsaved buffers

crates/gpui/src/app.rs

@@ -521,12 +521,27 @@ impl TestAppContext {
             .downcast_mut::<platform::test::Window>()
             .unwrap();
         let mut done_tx = test_window
-            .last_prompt
-            .take()
+            .pending_prompts
+            .borrow_mut()
+            .pop_front()
             .expect("prompt was not called");
         let _ = done_tx.try_send(answer);
     }
 
+    pub fn has_pending_prompt(&self, window_id: usize) -> bool {
+        let mut state = self.cx.borrow_mut();
+        let (_, window) = state
+            .presenters_and_platform_windows
+            .get_mut(&window_id)
+            .unwrap();
+        let test_window = window
+            .as_any_mut()
+            .downcast_mut::<platform::test::Window>()
+            .unwrap();
+        let prompts = test_window.pending_prompts.borrow_mut();
+        !prompts.is_empty()
+    }
+
     #[cfg(any(test, feature = "test-support"))]
     pub fn leak_detector(&self) -> Arc<Mutex<LeakDetector>> {
         self.cx.borrow().leak_detector()

crates/gpui/src/platform/test.rs

@@ -4,11 +4,12 @@ use crate::{
     keymap, Action, ClipboardItem,
 };
 use anyhow::{anyhow, Result};
+use collections::VecDeque;
 use parking_lot::Mutex;
 use postage::oneshot;
 use std::{
     any::Any,
-    cell::{Cell, RefCell},
+    cell::RefCell,
     path::{Path, PathBuf},
     rc::Rc,
     sync::Arc,
@@ -36,7 +37,7 @@ pub struct Window {
     event_handlers: Vec<Box<dyn FnMut(super::Event)>>,
     resize_handlers: Vec<Box<dyn FnMut()>>,
     close_handlers: Vec<Box<dyn FnOnce()>>,
-    pub(crate) last_prompt: Cell<Option<oneshot::Sender<usize>>>,
+    pub(crate) pending_prompts: RefCell<VecDeque<oneshot::Sender<usize>>>,
 }
 
 #[cfg(any(test, feature = "test-support"))]
@@ -188,7 +189,7 @@ impl Window {
             close_handlers: Vec::new(),
             scale_factor: 1.0,
             current_scene: None,
-            last_prompt: Default::default(),
+            pending_prompts: Default::default(),
         }
     }
 }
@@ -242,7 +243,7 @@ impl super::Window for Window {
 
     fn prompt(&self, _: crate::PromptLevel, _: &str, _: &[&str]) -> oneshot::Receiver<usize> {
         let (done_tx, done_rx) = oneshot::channel();
-        self.last_prompt.replace(Some(done_tx));
+        self.pending_prompts.borrow_mut().push_back(done_tx);
         done_rx
     }